Multiple contact receptacle for printed circuit boards and the like



March 9, 1965 J. LALONDE 3,172,718

MULTIPLE co RECEPTACLE FOR PRINTED CIRCUIT ans AND THE LIKE Filed March 20, 1963 INVENTOR. 60/ (4 New:

United States Patent M 3,172,718 MULTIPLE CONTACT RECEPTACLE FOR iPEKKhEISITED CIRCUIT BOARDS AND THE Guy I. Lalonde, Whitestone, N.Y., assignor, by mesne assignments, to Electronic Fittings Corporation, Danbury, Conn., a corporation of New York Filed Mar. 20, 1963, Ser. No. 266,695 4 Claims. (Cl. 339-176) This invention relates to electrical connectors and particularly such as are capable of making multiple electrical connections with a dielectric card or board having printed circuits thereon.

In certain multiple connection installations it is desirable to wrap the ends of the connecting wires around the shank of each of the individual connector elements. For this purpose, square or rectangular shaped shanks have been employed to improve the connection.

Previously known connector elements made for wrapped contact use have consisted of a rectangular length of metal to one end of which there is secured a flat spring member as by welding, brazing or the like. This construction in addition to requiring difficult fabricating op erations cannot be varied for a given stock size. The contact, stamped from conventional fiat spring stock must be worked in the quarter or half hard state and then brought to temper. The contact members as a result have reduced performance and reliability with reference to contact pressure and deflection.

Accordingly, it is an object of the present invention to provide a tapered leaf spring having a square shank portion which will give uniform pressure over the full spring deflection.

Another object of the present invention is to provide a leaf spring contact element formed of a single piece of metal which has as an integral part thereof a square shank portion suitable for wire wrapped connection.

Still another object of the present invention is to provide a contact structure which may be coined to a variable thickness depending upon the spring tension desired.

Still another object of the present invention is to provide a multiple contact assembly in cooperation with a plurality of spring contact members which will lock the spring contact members in place and also permit easy assembly and wiring.

The invention consists of the construction, combination and arrangement or" parts, as herein illustrated, described and claimed.

In the accompanying drawing forming a part hereof is illustrated one form of embodiment of the invention and in which:

FIGURE 1 is an isometric fragmentary view, partly broken away, of an embodiment of the present invention.

FIGURE 2 is a cross sectional view of the electrical connector block on an enlarged scale made in accordance with the present invention showing the contact members secured therein.

FIGURE 3 is a top plan view of the electrical contact block with certm'n of the connectors removed for the purposes of illustration.

FIGURE 4 is a view in side elevation of a tapered spring contact member, shown in FIGURE 2.

FIGURE 5 is a fragmentary view in front elevation of the spring portion of the contact shown in FIGURE 4.

Referring to FIGS. 1, 2 and 3, an elongated contact block of insulation is formed with a center slot 11 extending along the longitudinal axis of the block. A plurality of compartment defining walls 12 extend inwardly from each side of the slot wall toward the center. The walls 12 are spaced from each other as indicated at 13 to 3,172,718 Patented Mar. 9, 1965 receive therein contact members 14. Stop members 15 are molded into the contact block 10 between the walls 12 and limit the outward travel of the spring portions 16 of the contact members 14.

A contact locking base completes the block assembly and consists of outwardly extending fiangelike members 18 and a raised base portion 19. An elongated rib 20 is formed on top of the raised base portion 19 and abuts the bottom wall 21 of the contact block 10. A plurality of upstanding tongues 22 are carried by the rib 20 and are received within openings 23 in the bottom wall 21 that also defines the bottom of the elongated slot 11. The tongues 22 serve to lock the contact members 14 within the contact block 10.

As shown in FIGURES 1, 2 and 4, the shank 24 of the contact members 14 is provided with spaced, outwardly extending locking cars 25 which are struck from the shank 24. The ears 25 snap over and under the bottom wall 21 of the elongated slot 11 as the tongues 22 force the contact members 14 apart. The lower portion of the shanks 24 of the contact members 14 extend through square openings 26 in the raised base portion 19. These openings prevent the contact members 14 from twisting within the block 10.

It will be seen from FIGURES 2, 4 and 5, that, in addition to the square shanks of the contact members 14, there is provided a tapered leaf spring portion 16 as an integral portion of the contact member 14. The contact member 14 is formed from half hard square Phosphor bronze stock which is brought to spring temper by virtue of the forging operation Within the forming die. The tapered leaf spring 16 may be coined to any variable thickness depending upon the spring tension desired while maintaining the necessary square shank. The spring portion 16 is tapered in thickness from the shank portion 24 upwardly to provide the desired pressure on the printed circuit elements (not shown) which are to be forced between the spring portions 16 within the elongated slot 11. In this manner, the desired pressure against the dielectric card or board having printed circuits thereon can be maintained to insure positive wiping contact between the spring portion 16 and a printed circuit card.

The multiple connector assembly may be secured to any convenient support by means of the studs 27 which are carried at each end of the block 10.

In using this connector assembly, it is merely necessary to drop the contact members 14 in related pairs into the block 10 through the openings 23 in the bottom of the elongated slot 11. The square shanks 24 are then slid through the square openings 26 in the raised base portion 19. Thereafter the locking base is put in place and the tongues 22 are forced into the openings 23 to space the respective pair of contacts and firmly lock the contact members 14 in place by means of the outwardly extending ears 25. The bottom portions of the shank 24 which extend through the'openings 26 in the contact locking base may be wrapped in well-known manner.

When it is desired to disassemble the multiple connector assembly as for rewiring or repair, the contact locking base is simply pried from the contact block 10 to release the contact members 14 from the openings 23.

Each of the spring contact members 16 may be longi tudinally split or bifurcated as indicated at 28 to increase resilience of the contact.

My invention provides a novel contact member having a square base which is highly desirable for wire wrap contact and an integral tapered leaf spring portion which will insure highly efficient electrical contact with printed circuit boards inserted within the contact block. The assembly is easy to put together and wire and lends itself to ready disassembly and repair.

Having thus fully described the invention, what is claimed as new and desired to be secured by Letters Patent of the United States, is:

1. An electrical connector for a printed circuit board comprising an elongated dielectric block, an elongated slot in one side of said block disposed along the longi tudinal axis thereof, a plurality of spaced opposed compartment defining walls Within the slot extending from each side thereof and toward the center of the slot, a bottom wall in the block beneath the slot, an opening in the bottom wall between each of the opposed compartments, a unitary contact member in each of the compartments extending downwardly through the corresponding opening in the bottom wall, each contact comprising an elongated shank and a leaf spring portion on the shank disposed within its block compartment, a detachable locking base for the contacts comprising an elongated portion and a plurality of spaced tongues carried by and transversely extending from the base portion, said tongues being receivable Within the separate bottom wall openings respectively, each for spacing a pair 'of contacts and for locking the contacts within respective compartments in the dielectric block.

2. An electrical connector for a printed circuit board comprising an elongated dielectric block, an elongated slot in one side of said block disposed along the longitudinal axis thereof, a plurality of spaced opposed compartment defining walls within the slot extending from each side thereof and toward the center of the slot, 21 bottom wall in the block beneath the slot, an opening in the bottom wall between each of the opposed compartments, a unitary contact member in each of the compartments at opposite sides of said slot extending downwardly through the corresponding openings in the bottom wall, each of said contacts comprising an elongated shank of non-circular cross section and a leaf spring portion tapering in thickness from the shank disposed within each block compartment, a detachable locking base for the contacts comprising an elongated flangelike portion having a plurality of spaced, transversely extending tongues, a plurality of spaced openings corresponding to said shank cross-section in the flange-like portion in staggered relation to said tongues to receive the corresponding contact shanks, said tongues being receivable within the bottom wall openings to press the shank portions of said contacts against the corresponding side wall of the slot and lock the contacts within the dielectric block.

3. An electrical connector according to claim 2 in which the detachable locking base comprises spaced elongated flanges extending beyond the side walls of said block, a raised central portion between said flanges and a longitudinal ri-b to support the spaced tongues.

4. An electrical connector as specified in claim 1 wherein the bottom wall at the side Wall ends of each opening forms a shoulder and the shank portion of each contact has a pair of spaced locking ears for engaging opposite sides of said shoulder, and the tongue extending through said opening spaces a pair of contacts and holds them in their respective compartments in locked relation to said shoulder.

References Cited in the file of this patent UNITED STATES PATENTS 2,855,579 Wintriss Oct. 7, 1958 2,935,725 Fox May 3, 1960 2,946,033 Wirth July 19, 1960 3,101,231 Klostermann Aug. 20, 1963 FOREIGN PATENTS 235,622 Australia Sept. 25, 1961 

1. AN ELECTRICAL CONNECTOR FOR A PRINTED CIRCUIT BOARD COMPRISING AN ELONGATED DIELECTRIC BLOCK, AN ELONGATED SLOT IN ONE SIDE OF SAID BLKOCK DISPOSED ALONG THE LONGITUDINAL AXIS THEREOF, A PLURALITY OF SPACED OPPOSITE COMPARTMENT DEFINING WALLS WITHIN THE SLOT EXTENDING FROM EACH SIDE THEREOF AND TOWARD THE CENTER OF THE SLOT, A BOTTOM WALL IN THE BLOCK BENEATH THE SLOT, AN OPENING IN THE BOTTOM WALL BETWEEN EACH OF THE OPPOSED COMPARTMENTS, A UNITARY CONTACT MEMBER IN EACH OF THE COMPARTMENTS EXTENDING DOWNWARDLY THROUGH THE CORRESPONDING OPPENING IN THE BOTTOM WALL, EACH CONTACT COMPRISING AN ELONGATED SHANK AND A LEAF SPRING PORTION ON THE SHANK DISPOSED WITHING ITS BLOCK COMPARTMENT, A DETACHABLE LOCKING BASE FOR THE CONTACTS COMPRISING AN ELONGATED PORTION AND A PLURALITY OF SPACED TONGUES CARRIED BY AND TRANSVERSELY EXTENDING FROM THE BASE PORTION, SAID TONGUES BEING RECEIVABLE WITHIN THE SEPARATE BOTTOM WALL OPENINGS RESPECTIVELY, EACH FOR SPACING A PAIR OF CONTACTS AND FOR LOCKING THE CONTACTS WITHIN RESPECTIVE COMPARTMENTS IN THE DIELECTRIC BLOCK. 